1. Field of the Invention
The present invention relates to a multiband transmitting and receiving apparatus and method. More particularly, the present invention relates to a multiband radio frequency (RF) transmitting and receiving apparatus and a method that are capable of using a control voltage from a phase locked loop (PLL) to control other components as well as to control a voltage controlled oscillator (VCO) of a multiband RF transceiver.
2. Description of the Related Art
Recently, since various wireless communication services coexist, cellular phones capable of operating at dual-band or at tri-band have been actively researched. Unlike single-band cellular phones, which operate at only one frequency band, dual-band cellular phones can operate at two frequency bands (for example, 900 MHz and 1800 MHz), and tri-band cellular phones can operate at three frequency bands.
Efforts have already been made to combine various wireless communication devices. Producers of such wireless communication devices are required to manufacture products capable of operating at various frequency bands in order to satisfy the demands of users wanting additional functions. In addition, to reduce size and manufacturing cost, components used in such wireless communication devices need to operate at a number of different frequency bands. Therefore, there is now a demand for technology that can be used to combine IMT-2000, W-PAN (Wide band—Private Area Network), W-LAN (Wide band—Local Area Network), and the like, and for a single chip set capable of providing various services using only essential components.
Conventional techniques are either not capable of operating at multiple bands or not capable of operating at different frequency bands using a switch. Further, conventional techniques are complicated and can only be performed using highly complex structures.